code: def test_b_factor_shift():
      """Test b_factor shifting one white space when saving the fetched pdb."""
      ppdb = PandasPdb()
      ppdb.fetch_pdb("2e28")
      ppdb.to_pdb(path=OUTFILE, records=None)
      tmp_df = ppdb.read_pdb(path=OUTFILE).df["ATOM"]
      os.remove(OUTFILE)
      assert tmp_df[
          tmp_df["element_symbol"].isnull()
          | (tmp_df["element_symbol"] == "")
      ].empty
      assert not tmp_df[
          tmp_df["blank_4"].isnull() | (tmp_df["blank_4"] == "")
      ].empty
  
file_path: biopandas/biopandas/pdb/tests/test_write_pdb.py
imports: from biopandas.pdb import PandasPdb
  import warnings
  import pandas
  import os
label_desc: Use image node_id 7 for calling a global function with example usage: test_b_factor_shift() without return types